Importing large excel with different data types

Dear MatLab Users Community,

I would like to import 255 .xlsx files to the Matlab. Each file contains 3500 columns; the number of rows varies. The data types of columns also vary: date-floating-text-floating 895 times further columns. The example of the data is:

02P GY Equity        0RY GY Equity        0TS GY Equity      
8/4/2011  3600     NoValue  3600  3/16/2016  9271      NoValue  9271  3/22/2016  2376  NoValue  2376
8/8/2011  2125     NoValue  2125  4/1/2016   1188      NoValue  1188  3/24/2016  388.35  NoValue  388.35
8/17/2011  8369    NoValue  8369  4/6/2016   9932.4   NoValue  9932.4  3/31/2016  203.3  NoValue  203.3
8/18/2011  5097.5  NoValue  5097.5  4/8/2016   34888.75 NoValue  3488.75 4/7/2016  3954  NoValue  3954
8/22/2011  1992.6  NoValue  1992.6  4/19/2016  1563.5   NoValue  1563.5  4/8/2016  400  NoValue  400
8/23/2011  975     NoValue  975          4/28/2016  50.54    NoValue  50.54  4/14/2016  665.36  NoValue  665.36
8/24/2011  481270  NoValue  481270                  4/18/2016  4101.63  NoValue  4101.63
8/26/2011  486     NoValue  486                          4/19/2016  874.8  NoValue  874.8
8/29/2011  18313.9 NoValue  18313.45                  4/21/2016  1510.42  NoValue  1510.42

How can I import 255 xls files of this type so that to have ONE matrix per each file?

I've tried using this code below, but it imported me "data" and "text data" matrices: Is there a way to import the files so that they look in MatLab similar to Excel?

d = dir('*.xlsx');
nfiles = size(d,1);
data = cell(1, nfiles); %preallocation for data line
for k = 1:nfiles;
    disp (k)
    data{k} = importdata(d(k).name);
end
clear nfiles

Thanks a lot!

Answer 1

[KL]

Try using readtable.

https://www.mathworks.com/help/matlab/ref/readtable.html

[Ekaterina Serikova]

As far as I understand, with this function I have to specify the type of each column. Given that I have 3500 columns, I should then indicate 3500 types for each column, is that right?

[KL]

If your excel files are properly formatted, you just need to write like, readtable(d(k).name), and it should work!

[Image Analyst]

No, that's not right. Why do you think you need to indicate what type of data each column is? You don't. It figures it out. You could also use xlsread

[numbers, strings, raw] = xlsread(.....

[Ekaterina Serikova]

Dear Image Analyst, if I need to import several xlsx files in a loop so that for each file a separate matrix is created, how can I do this?

[Image Analyst]

Make a cell array to hold them all, but I seriously doubt you need to do this. Why can't you just use raw within the loop? Why do you need to save ALL raw cell arrays?

% Get worksheet for just this file:
[~, ~, thisRaw] = xlsread(.....
% thisRaw is a cell array from just this one particular file.
% Save this one into one cell of our cell array that holds all the raw cell arrays.
allRaw{k} = thisRaw;

Now allRaw is a cell array were each cell of that cell array contains another cell array. You like to complicate your life, don't you. Please read the FAQ so you have a chance of understanding this: FAQ entry on cell arrays